Outdoor grilling systems which utilize infrared radiant energy for cooking food items are known in the art. The beneficial results which these systems are capable of providing over conventional convective grills are also well known. However, there are various shortcomings and deficiencies which are often associated with many current infrared systems.
Even if formed of a common stainless steel or similar material, most food support grates heretofore used in infrared and other outdoor grills will begin to rust after a relatively short period of use. This oxidation process not only shortens the life of the grate, but the particles and/or flakes of the oxidized rust material which form on the grate surface also adhere to the food product.
To prevent rust from forming on the food contacting surface, the grate can be formed of a metal material which is highly resistant to rusting. However, such materials are cost prohibitive for use in most grilling systems and/or are not well suited for grilling at high temperatures.
Alternatively, or in addition, the grate could be coated with a coating material which is highly resistant to oxidation even at high temperatures. However, coating a cooking grate with such material can also be cost prohibitive for most grilling apparatuses. Moreover, the application of such a coating to an infrared grate can clog any air flow openings through the grate surface and can create other problems and difficulties which will increase both the complexity and the cost of the manufacturing process.
Another serious deficiency encountered with current infrared cooking grates is their susceptibility to flare-ups caused by the ignition of fat and grease materials which collect on top of the grate during cooking. Such flare-ups have a significant detrimental effect on the quality, consistency, reliability, and evenness of the cooking process.
Moreover, the collection of the fat and grease materials also interferes with and reduces the emission of infrared cooking energy from the grate. In addition to forming a coating on the grate surfaces, the grease and fat will also cool the emitting surfaces of the grate significantly. In this regard, the grease and fat which drips from a meat product while cooking will typically be at a temperature of about 120°-460° F. when it first strikes the grate. Consequently, the resultant energy transfer and temperature loss from the grate which occur as the grate heats the accumulated grease and fat to an ignition temperature of about 600°-650° F. can be substantial.
In an effort to prevent flare-ups from occurring on the top of some prior two-piece grate assemblies having flat lower radiating plates, holes have been provided through the flat plates for draining the grease and fat. In some cases, the placement of the upper grate element on top of the flat lower plate element forms substantially rectangular channels wherein the holes are located. However, in these prior two-piece grate designs and configurations, the nature and large size of the holes needed to quickly and effectively drain the grease and fat from the flat lower plate before it reaches ignition temperature would, in actuality, simply result in one flare-up problem being replaced with another. Specifically, with the addition of holes in the lower plate of a sufficient size to achieve quick drainage, the prior two-piece assemblies would no longer be capable of arresting flames caused by the flare-up of the grease and fat beneath the grate. Rather, the flames would pass upwardly through the drainage holes and into the cooking area.
Examples of further shortcomings and deficiencies commonly encountered in existing infrared grilling systems include: cleaning difficulties created by small gaps, crevices, and other features which can be difficult to reach; the need to use expensive infrared burners or other high-cost heating systems in order to provide the degree of performance and results desired; and the need to use a separate infrared emitter plate or other emitting structure positioned intermediate the burner and the food support grate or grate assembly.
Consequently, a need currently exists for an improved cooking grate assembly for infrared grills which will: (a) provide a substantially rust-free food contacting surface throughout the useful life of the grill; (b) provide high efficiency operation and a high infrared percentage of overall heat flux; (c) reduce or eliminate flare-ups on top of the grate assembly; (d) reduce or eliminate the penetration of flames upwardly through the cooking surface; (e) allow low cost burners or other heating elements or heat sources to be used for providing excellent cooking results; (f) eliminate the need for a separate emitter plate or other structure intermediate the burner and the grate assembly; and (g) accomplish these results without increasing the complexity or difficulty of the manufacturing process.